<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        h3,h1,h2,h4,h5,h6,
        p,
        ul,
        dl,
        dt
        {
            margin: 0;
        }
        a{
            text-decoration: none;
        }
        ul{
            list-style: none;
        }
    </style>
</head>
<body>
    <h3>h3</h3>
    <p>p</p>
    <ul>
        <li>1</li>
        <li>2</li>
        <li>3</li>
    </ul>
    <dl>
        <dt>dt</dt>
        <dd>dd</dd>
    </dl>
    <a href="">a标签</a>
</body>
</html>